Coping with a clay soil can be one of the most
challenging aspects of gardening, particularly for beginners.
But don't despair, I'd much rather have
a clay soil than chalky or sandy, it's just a question of learning
how to make the most of what you have got.
Good things about clay soil
Characteristically slow to dry out
Able to "lift" water from the water table by capillarity
Established plants frequently survive drought periods well
even if they are not watered through them
Usually very rich in nutrients
Plants that survive the first couple of years on clay tend
to grow and survive very well with little intervention
Bad things about clay soil
Always heavy to work
to warm up in spring
Can get waterlogged
Plants planted into clays generally take longer to establish
than on other soils
Growth can be fairly slow at first
Having a clay soil
can seem very unfair. Like when you were at school, - you're
going to do something new and the teacher brings out the equipment.
But instead of paying attention, you were talking to your friend or
daydreaming or at the toilet. Then when there's the mad scramble
for the stuff, you get left with every body else's rejects. You
know it's going to be difficult, but most of all it just doesn't
If you've got clay
soil, then you're probably acutely aware of the fact, but if you're
not sure, then take a little moist or wet soil in your fingers and rub
it gently, If it "polishes" i.e. makes a shiny smooth coating
on your fingers and is greyish brown in colour it's probably clay.
Dealing with clay
- There are three key elements to improving clay
The weather helps to break the soil up in the winter by a freeze / thaw effect
on the clods that you dig up. Digging the soil over in the autumn
and then leaving it for the weather to act upon is the most effective
way of breaking it up. In the spring, the soil can be broken down
much more easily into a fine tilth by raking.
is the way that you can improve the soil in the longer term. Garden
compost, farmyard or stable manure and in large quantities, the
bulkier the better. Dig it in if you can, but if there's just
too much, then apply it as a thick layer of mulch in the autumn
and then leave it for the worms to take down into the soil for you
- slower, but effective. Also, whenever you do any work in the garden,
you will work the organic matter into the soil as a side-effect.
is the third key element. Really it means repeating the above two,
for several years. It will take a few years, 3, 4 or even up to
10 of digging and adding bulky organic matter to really improve
the soil for the long term. So keep on going!
- If you have clay soil, never walk on it when it
wet, you will compact it even more squashing out any
pockets of air that it may contain and leaving it to
develop a hard and caked surface when it dries out.
- Knowing when to dig becomes a bit of a fine art
in fact. Too wet and it's horribly sticky, too dry
and it's horribly hard. I find a mattock (like a
pick-axe, but with a large flat horizontal blade on
one end) very useful if I have to work on a hard dry
- Use a fork rather than a spade to dig the soil.
- Take more smaller bites with the fork, rather than
trying to move too much soil in one go.
There are a great
many more plants that will grow on clay soil, but these are consistent
Flowers and ornamentals
grow really well in clay soils, they have strong
roots that get through it, the clay then provides
plenty of nutrients a good anchor against wind rock
and a ready supply of water that the rose roots
can go and find.
big trendy grass-like plants with broad sword-like
leaves from New-Zealand. Similar reasons to roses,
| Amelanchier, June
Berry / Shadbush, white spring flowers and
bronze new foliage
Cuban laurel, yellow spotted green leaves.
thunbergii. Versatile and varied group
- Ornamental or Japanese quince.
Masses of beautiful red to pale pink
flowers depending on variety borne on bare stems
when much of the rest of the garden is still dormant.
ternata, Mexican orange blossom, Glossy
evergreen shrubs that comes in two main types grown
either for wonderfully fragrant white flowers in
summer (and often again in autumn) with green leaves,
or for vibrant yellow leaves in the variety "Sundance"
which unfortunately rarely flowers.
varieties - Dogwoods One of the best shrubs
for waterlogged areas for most gardens. Dogwoods
are often grown for their winter stem colour which
is red or yellow. There are also varieties with
attractive variegated leaves.
Buy Cornus / doqwoods
varied group of shrubs from small to tree like,
white flowers, berries in autumn of various colours.
golden leaved evergreen, good for hedging too.
especially x media)
spiky white spring flowered autumn berried extremely
Taxus baccata, English Yew, for a very
formal hedge or as a specimen.
coignetiae - Crimson glory vine
One of my favourite climbers
this one, large bright green heavily textured leaves up
to 12" across whose autumn colours earn it its common
Buy Vitis coignetiae
Fruit and Veg
the traditional crop to break up clay, they don't need
a fine tilth, they can push their large strong roots and
tubers through the soil and the act of earthing up helps
break the soil up and suppress weeds. Main crop or late
rather than early varieties as clay soils are slow
to warm up in spring.
/ French / Broad beans, Peas. When the crop is over
cut the plants off at soil level, leave the roots to rot
under ground so adding organic material and nitrogen from
the root nodules that the plants form.
cabbages, brussels, kale (not cauliflowers though).
Main crop or late rather than early varieties as clay
soils are slow to warm up in spring.
most types do well as long the soil is not waterlogged
at any time.
- Apples, Pears and Plums in particular.
Root crops such as
carrots and parsnips, they have difficulty in growing through
the heavy soil and often end up with forked roots (unless
you like the idea of growing "rude" carrots).
Any kind of early crops
including salads, unless the soil has been warmed in
advance by using a cloche, cold-frame or plastic tunnel.
Extreme clay soil